Apple's iMessage to Finally Get Major Update at WWDC?

Apple has put iMessage at the center of its promotional materials for WWDC next week, hinting that the company's popular messaging service could be seeing substantial upgrades.
iMessage appears to be a central theme in the marketing for this year's WWDC. For example, the placeholder for WWDC's live stream on YouTube, which is already live, features iMessage bubbles, Tapback, and iMessage's full-screen laser effect. Similarly, the Twitter hashflag to promote WWDC this year is an iMessage thumbs-u